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arXiv · 2507.01720

Laser cooling and qubit measurements on a forbidden transition in neutral Cs atoms

J. Scott·H. M. Lim·U. Singla·Q. Meece·C. Fang·J. T. Choy·S. Kolkowitz·T. M. Graham·M. Saffman
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Abstract

We experimentally demonstrate background-free, hyperfine-level-selective measurements of individual Cs atoms by simultaneous cooling to $5.3~\mu\rm K$ and imaging on the $6s_{1/2}\rightarrow 5d_{5/2}$ electric-quadrupole transition. We achieve hyperfine resolved detection with fidelity 0.9993(4) and atom retention of 0.9954(5), limited primarily by vacuum lifetime. Performing state measurements in a 3D cooling configuration enables repeated low loss measurements. A theoretical analysis of an extension of the demonstrated approach based on quenching of the excited state with an auxiliary field, identifies parameters for hyperfine-resolved measurements with a projected fidelity of $\sim 0.9995 $ in $\sim 60~\mu\rm s$.

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J. Scott, H. M. Lim, U. Singla, Q. Meece, C. Fang, J. T. Choy, S. Kolkowitz, T. M. Graham, M. Saffman. 2025-07-02. Laser cooling and qubit measurements on a forbidden transition in neutral Cs atoms. https://doi.org/10.1103/j4h9-fdvh

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